24 Monarch

Danaus plexippus

Characteristics

Wingspan: 3.5–4 in (89–102 mm).

Flight season: All year in southern United States.

Nectar sources: Milkweeds.

Habitat: Meadows, farmland, roadside verges.

The monarch is renowned for its bright appearance and long migratory flights. It is one of the best-known butterflies, even among people who have never seen one in the wild. The male’s upperwings are bright orange, those of the female orange-brown. Both sexes have wide black borders and veins, the black borders spotted with white. Monarch populations in tropical regions are mostly resident, but at higher latitudes they are migrants. In fall, millions migrate from the eastern United States and southern Canada to central Mexico, where they roost in trees during the winter and become active on warm days to fly in search of nectar.

In spring, most migrant monarchs mate before setting off on long journeys that will take some as far north as Canada. The females lay eggs singly under the leaves of milkweeds along the way. These are also their preferred nectar flowers, but early in the season, before they bloom, monarchs visit lilacs, red clover, thistles, and dogbane. There may be up to six broods in Mexico and the southern United States, perhaps just one in the far north of their range.